What does a CT scan of the lungs show?
Thin sections show lesions and infiltrates, “ground glass” in viral pneumonia with an assessment of the percentage of damage, nodes from 2–3 mm (important for early detection of cancer), cavities, bronchiectasis, emphysema, fibrosis, enlarged mediastinal lymph nodes, fluid in the pleura, pneumothorax, rib fractures. Chest CT is recommended for lung cancer screening in smokers over 50 years of age annually in a low-dose regimen. To evaluate tumors and lymph nodes, the study is supplemented with intravenous contrast.
Indications
- pneumonia, including viral, and its complications, assessment of the volume of lung damage;
- suspicion of a lung tumor, nodes on x-ray, screening for lung cancer in smokers;
- tuberculosis, sarcoidosis, interstitial diseases, bronchiectasis;
- chest injury, rib fractures, pneumothorax;
- prolonged cough, shortness of breath, hemoptysis of unknown cause;
- diseases of the esophagus (tumors, diverticula, strictures) - with contrast.
What is MSCT
Multislice computed tomography is a layer-by-layer X-ray study in which detectors receive dozens of sections up to 0.5–1 mm thick in one revolution of the tube, and a computer builds a three-dimensional image of the organ. MSCT is performed in 5-15 minutes, accurately shows bones, lungs, stones, hemorrhages, tumors and vessels (with contrast), and is often the method of choice for trauma and acute conditions when MRI is too long or contraindicated.
Preparation and contrast
Non-contrast MSCT does not require preparation. Before a study with intravenous contrast, a test for creatinine (kidney function) and the absence of an allergy to iodine are required; 4–6 hours without eating; When taking metformin, agree on a break with your doctor. Contrast (Unigexol) is administered using an automatic injector; a feeling of warmth for 1–2 minutes is normal. To examine the abdominal and pelvic organs, oral contrast is used, which is drunk 30–60 minutes before the scan. Remove metal objects from the examination area. The radiologist’s conclusion is completed within 1–2 hours, the images are issued on film and disk.
Radiation exposure and safety
Modern devices use low-dose protocols; the dose for one study is comparable to several months of natural background and does not accumulate dangerously when prescribed appropriately. MSCT is not performed on pregnant women (except for vital indications); for children - according to strict indications with a minimum dose. Iodine contrast is contraindicated in severe renal failure, iodine allergy and uncontrolled hyperthyroidism. Pacemaker and metal implants are not a contraindication, unlike MRI.
